Beginner

Suited for a wide range of uses, Level 1 Beginner telescopes are simple to operate and set up. Some initial assembly may be required. Very good optical and mechanical quality. Great for families, young people, and folks who don't want to mess with equipment but just want to take a look. Any of these scopes will show you countless lunar craters, Saturn's rings and a myriad of star clusters and nebulas! Referring to the manual is recommended.

Take a guided tour of the cosmos without leaving the comfort of your own backyard! The value-packed StarSeeker III 90mm GoTo Mak-Cass Telescope Kit is a great setup for beginning amateur astronomers since it's loaded with so many great accessories and a complete GoTo telescope system.

The self-pointing Orion StarSeeker III 90mm GoTo Maksutov-Cassegrain Telescope will show you and your family interesting celestial sights on any clear night. Its compact 90mm Maksutov-Cassegrain optical tube assembly makes it the most portable member of the StarSeeker III family of GoTo telescopes. What's more, the StarSeeker III 90mm features a smaller altazimuth mount than its brethren for easy transport. The most portable StarSeeker III boasts a long 1250mm focal length and f/13.9 focal ratio for exceptional high-power performance.

An excellent choice for intrepid beginning amateur astronomers, the user-friendly, fully computerized StarSeeker III 90mm GoTo telescope provides electronic, motorized navigation to all the finest celestial objects. StarSeeker III models boast an upgraded computerized database of over 42,000 celestial objects to explore. Once the GoTo system locates a selected object, the StarSeeker III 90mm Mak-Cass will precisely track it as it appears to move across the night sky, so you can enjoy the view for as long as you like before selecting a different target. This allows you to relax and enjoy the view instead of fumbling with cables and buttons to keep the object centered.

Lightweight at just 10.7 lbs. when fully assembled, the easily portable StarSeeker III 90mm GoTo Maksutov-Cassegrain packs a big performance punch in its small telescope tube. Maksutov-Cassegrain telescopes employ both mirrors and lenses to "fold" the light path, which keeps them conveniently compact in size, but with the high magnifying abilities of much longer refractor or reflector models. This gives the StarSeeker III 90mm Mak-Cass a winning combination of easy portability and powerful optics. What's more, the included single-arm GoTo altazimuth mount can be set-up and taken down quickly, and features a quick-release dovetail saddle for swift telescope attachment without the need for tools.

Following an easy two-star alignment process, the StarSeeker III 90mm GoTo can take you on a guided tour of the best visible objects in the night sky. Once aligned, this smart telescope will find and aim itself at any visible planet or Messier, NGC, or IC catalog object in seconds with just a few button pushes. Built-in encoders and servo motors slew the telescope accurately and automatically right to the object you select from the GoTo hand controller's intuitive menus. With a vast database of over 42,000 celestial objects, the StarSeeker III 90mm GoTo Mak-Cass will show you interesting sights on any clear night.

Since the StarSeeker III 90mm Mak-Cass can locate and track celestial objects with its motorized GoTo system, you can use it along with a camera or smartphone to take impressive pictures of the night sky. Capture stunning snapshots of the Moon, planets and more by attaching a dedicated astrophotography camera, or a combination of an Orion SteadyPix accessory and your own point-and-shoot camera or smartphone to the StarSeeker III 90mm Mak-Cass to explore the rewarding hobby of astrophotography. (Cameras and SteadyPix accessories sold separately.)

You'll get a great assortment of useful accessories with the StarSeeker III 90mm GoTo Maksutov-Cassegrain Telescope Kit:

Two 1.25" eyepieces are included with the StarSeeker 90mm GoTo Mak-Cass.

The included 25mm Explorer II eyepiece provides 50x magnification in the 90mm Maksutov-Cassegrain optical tube, and the 10mm yields 125x for higher-power looks through the telescope. We recommend starting with the 25mm eyepiece every night to observe a wider area of the night sky, then boost magnification by swapping out the 25mm eyepiece with the 10mm ocular once you have an object centered.

Use the included 90° star diagonal to view the night sky comfortably.

A diagonal "bends" the light path of a telescope so you can enjoy the view without having to contort yourself into awkward positions to peer into the eyepiece. The 90° star diagonal that comes with the StarSeeker 90mm GoTo Mak-Cass places the eyepiece you're using in a comfortable position for nighttime stargazing of the skies above.

Use the included EZ Finder II reflex sight to help center initial alignment stars when performing the two-star alignment required for accurate GoTo performance. It's a non-magnifying sighting device that superimposes a tiny, LED-powered red dot, focused at infinity, on the sky. After a simple alignment procedure, the red dot shows exactly where your telescope is pointed.

Let the computerized GoTo controller guide you on a tour.

The StarSeeker III 90mm GoTo Mak-Cass lets you explore the skies with pushbutton ease thanks to its GoTo hand controller. With a vast database of over 42,000 celestial objects including stars, double stars, galaxies, nebulas, star clusters, and more, the included computerized GoTo hand controller will become your tour guide to the skies.

The StarSeeker III 90mm GoTo Mak-Cass also includes a compass, PC interface cable, and a removable accessory tray for the tripod. Each StarSeeker III requires 8 AA batteries (not included) or an external 12V DC field battery or AC-to-DC wall adapter.

Our most portable StarSeeker III Mak-Cass is better than ever when used with the extra accessories in this value-packed kit.

Use the Shorty 2x Barlow with the 25mm eyepiece that comes with the 90mm Mak-Cass to enjoy 100x magnification compared to 50x, and the combination of the 10mm eyepiece and Barlow bumps the power from 125x to a very powerful 250x view. Use the included MoonMap 260 to properly identify lunar features you see through the telescope. Read the Discover the Stars guidebook to learn helpful hints about stargazing. Use the Star Target Planisphere to see what constellations and objects will be visible on any day of the year. The RedBeam Mini flashlight makes it easy to refer to charts and books while observing, and it helps you see small parts and knobs without disrupting dark-adapted vision.

Warranty

Limited Warranty against defects in materials or workmanship for one year from date of purchase. This warranty is for the benefit of the original retail purchaser only. For complete warranty details contact us at 800-676-1343.

User level

Level 1 Beginner - Suited for a wide range of uses, these telescopes are simple to operate and set up. Some initial assembly may be required. Very good optical and mechanical quality. Great for families, young people, and folks who don't want to mess with equipment but just want to take a look. Any of these scopes will show you countless lunar craters, Saturn's rings and a myriad of star clusters and nebulas! Referring to the manual is recommended.

Level 2 Intermediate - These scopes offer higher performance and more advanced features than Level 1: Beginner models. They typically take a bit longer to learn and need some set-up or adjustments. But anyone with the slightest technical bent will have no problem getting familiar with these models. Referring to the manual is recommended.

Level 3 Advanced - These scopes provide the best performance but may require more skill to master and appreciate. They have exceptionally fine optics and mechanics. Some are easy to use but are but on the large or heavy side. Some are intended for specialized uses. These scopes will appeal to the more technically inclined. Referring to the manual is highly recommended.

Level 4 Expert - Expert telescopes offer uncompromising optical and mechanical quality for the most demanding amateur astronomer. They may be technically involved or designed for specialized use, such as astrophotography or detailed deep sky observation. They carry a premium price, but are designed to provide the ultimate performance in the field. Referring to the manual is highly recommended.

Optical design

Reflector telescopes use a pair of large and small mirrors to direct incoming light to the eyepiece.
Refractor telescopes refract, or "bend" incoming light to a focus by means of an objective lens.
Cassegrain telescopes, such as Maksutov-Cassegrains, "fold" incoming light using two mirrors and a front "corrector" lens.

Optical diameter

For telescopes, the optical diameter (also known as aperture) is the size of a telescope's main light-collecting lens or primary mirror, measured in millimeters or inches. Telescopes with larger optical diameters collect more light, which leads to an increase in brightness and image resolution compared to smaller instruments.

For binoculars, the optical diameter (also known as objective lens diameter) is the size of each of the front-facing objective lenses of a binocular measured in millimeters. Binoculars with larger objective lenses collect more light, which increases image resolution and brightness. Binoculars with larger objective lenses are recommended for low light situations, and binoculars with at least 50mm or larger objective lenses are recommended for pleasing astronomical observations at night.

Focal length

The distance from the center of a curved mirror or lens at which parallel light rays converge to a single point. The focal length is an inherent specification of a mirror or lens and is one of the factors in determining resultant magnification for a telescope (along with the focal length of the eyepiece being used).

Focal ratio

The focal ratio of an optical system is the ratio of a telescope's focal length to its aperture. Short focal ratios (f/5, f/4.5) produce wide fields of view and small image scales, while long focal lengths produce narrower fields of views and larger image scales.

Optics type

Newtonian reflectors will have either a spherical shaped mirror, which is less expensive to produce, or a higher quality parabola, which does not result in spherical aberration. Cassegrain telescopes routinely use spheres in addition to other lenses in the optical path to correct for residual spherical aberration.
Refractors use a series of lenses to provide a clear image. Designs range from a standard air-spaced doublet (two lenses in a row) to exotic designs such as oil-spaced triplets and 4-element multi group lenses.

Resolving power

The theoretical resolving power of a telescope can be calculated with the following formula: Resolving power (in arc seconds) = 4.56 divided by aperture of telescope (in inches). In metric units, this is: Resolving power (in arc seconds) = 116 divided by aperture of telescope (in millimeters). Note that the formula is independent of the telescope type or model, and is based only upon the aperture of the telescope. So the larger the telescope's aperture, the more it is capable of resolving. This is important to keep in mind when observing astronomical objects which require high resolution for best viewing, such as planets and double stars. However, it is usually atmospheric seeing conditions (not the telescope) which limits the actual resolving power on a given night; rarely is resolution less than one arc-second possible from even the best viewing locations on Earth.

Lowest useful magnification

Lowest useful magnification is the power at which the exit pupil becomes 7mm in diameter. Powers below this can still be reached with the telescope to give wider fields of view, but the image no longer becomes brighter at a lower power. This is due to the fact that the exit pupil of the telescope (the beam of light exiting the eyepiece) is now larger than the average person's dark adapted pupil, and no more light can fit into the eye.

Highest useful magnification

The highest practical limit is different from the often used "highest theoretical magnification" specification. The "theoretical" limit generally is 50x the aperture of the scope in inches (2x the aperture in mm). So for example, an 80mm refractor is capable of 160x, and a 10" telescope is theoretically capable of 500x magnification.
But after approximately 300x, theory breaks down and real world problems take over. The atmosphere above us is constantly in motion, and it will distort the image seen through the telescope. This effect may not be noticeable at lower powers, but at higher powers the atmosphere will dramatically blur the object, reducing the quality of the image. On a good night (a night where the air above is steady and the stars aren't twinkling), the practical upper limit of a large telescope is 300x, even thought the theoretical limit may be much higher. This doesn't mean the scope will never be able to reach those higher "theoretical" powers - there will be that rare night where the atmosphere is perfectly still and the scope can be pushed past it's practical limit, but those nights will be few and far between.

Astro-imaging capability

The astro-photographic capability of the telescope is based on the style, stability, and accuracy of the mount and tripod. Telescopes on either very lightweight mounts or non tracking mounts (such as Dobsonians) are capable of only very short exposures such as lunar photographs. If a motor drive is attached to an equatorial mount, even a small lightweight mount is capable of capturing some planetary detail. Larger EQ mounts that utilize very precise tracking and excellent stability are capable of longer exposure deep-sky photography.

Computerized compatibility

Some mounts are compatible with a motorized Go-To system for fully automated computer finding of objects in the night sky. Others mounts are compatible with computer finding systems which require the user to manually move the mount to the object's position as indicated by the computer finder.

GPS

A GPS module automatically sets the date and exact time and location for the mount, relieving the user from the need to look up coordinates on a map or manually enter perfect time. This can be very beneficial when traveling with the scope as locations can quickly be automatically entered into the hand control.

Height range of mount

The height range specification is a measure of the tripod itself - not the eyepiece height. Since telescopes come in all shapes and sizes, the eyepiece height will vary, even when using the same tripod. For an EQ tripod the mount is set up so the counterweight shaft is horizontal, and then the height is measured from the ground to the center of the mounting plate.

Warranty

This warranty gives you specific legal rights. It is not intended to remove or restrict your other legal rights under applicable local consumer law; your state or national statutory consumer rights governing the sale of consumer goods remain fully applicable.

Orders received by 1pm Eastern Time for in-stock items ship the same business day. Orders received after 1pm will ship the next business day. When an item is not in-stock we will ship it as soon as it becomes available. Typically in-stock items will ship first and backordered items will follow as soon as they are available. You have the option in check out to request that your order ship complete, if you'd prefer.

This value-packed telescope kit is an excellent choice for intrepid beginners. The computerized StarSeeker III 102mm GoTo Mak-Cass provides great views and the additional included accessories help you get the most out of every stargazing session.

Having trouble viewing details on the Moons surface? This neutral-density eyepiece filter reduces glare so you can see more detail and surface features. The 1.25" Orion 13% Transmission Moon Filter is especially useful with large aperture telescopes.

Orion Sirius Plossl eyepieces are ideal for any type of telescope, refractor, reflector, or catadioptic. They offer a 52° field with clean, high-contrast images. All air-to-glass surfaces are fully coated for improved light transmission.

This solar filter fits the Orion StarMax, Apex 90, and Meade ETX-90. The 4.10" Orion Full Aperture Solar Filter is a must for safely viewing or photographing the sun's surface. Provides more contrast and more natural color than Mylar filters.

A great tool for bringing out details in the planets and Moon is this 1.25" set of four Orion Color Telescope Filters. Each colored filter brings out different details in the planets allowing for a totally different view.

The Dynamo Pro 17Ah enables you to power your 12-volt astronomy gear during lengthy observing and/or astrophotography sessions in the field. Two convenient 5V USB outputs are also built-in to power USB devices and adapters.

Capture images of the Moon, planets, and Sun with the Orion StarShoot Solar System Color Imager IV. Small pixels provide exceptional resolution, and the included software allows the astrophotographer to process the images for fantastic results.

This easy-to-use mounting bracket securely holds your point-and-shoot camera or smartphone right up to your telescope's 1.25" eyepiece, at the perfect position and focus point, allowing you to capture high-magnification pictures of the night sky.

If you are an avid astronomer you know that you should always use red light instead of white to help protet your night vision. The Orion RedBeam II LED Flashlight has adjustable brightness which lets you observe without ruining your night vision.

Control your GoTo telescope wirelessly from your iPhone, iPad, or iPod touch with the StarSeek Wi-Fi Telescope Control Module, Serial/USB. It works with Orion motor-driven GoTo telescopes and many other brands, including USB port-equipped models.

At Orion, we are committed to sharing our knowledge and passion for astronomy and astrophotography with the amateur astronomy community. Visit the Orion Community Center for in-depth information on telescopes, binoculars, and astrophotography. You can find astrophotography "how to" tips and share your best astronomy pictures here. Submit astronomy articles, events, and reviews, and even become a featured Orion customer!